The well documented damaging consequence of the widespread, long-term use of fossil fuels has resulted in a global initiative for renewable, eco-friendly alternatives. Biodiesel has been recognized as a viable solution for many reasons, such as: it is 100% renewable, because it is derived from a plant that can be grown; it can be produced from virtually any vegetable oil; it is environmentally friendly to use and process, emitting 75%-80% lower emissions than petro-diesel; it extends engine life with increased lubricity; and it offers substantially greater energy per unit.
Biodiesel is widely used in Europe, claiming 12-15% of the fuel market, and growing in the U.S., particularly in the Midwest region of the country. In Germany, biodiesel is made primarily from rapeseed oil (AKA Canola Oil), while commercial biodiesel in the U.S. is derived largely from soybean oil. The fact that rapeseed and soybeans are edible crops is a major disadvantage. Utilizing any edible crops for fuel is not a desirable solution because this results in escalating the cost of food.
A crop of rapeseed produces 127 gallons of oil per acre per year, while soybean produces only 48 gallons of oil per acre per year. Producing biodiesel from rapeseed or soybean is not cost effective, and requires government subsidies to be marketed competitively as a fuel. The soybean-based biodiesel industry in the U.S. poses little rivalry to the petroleum industry. In most cases, biodiesel is dispensed as a 10% or 20% additive (B10 or B20) to petro-diesel, co-existing comfortably with the dominant fuel.
Another source of oil for biodiesel that is garnering increased interest is a plant called Jatropha curcus. Unlike soybean or rapeseed, Jatropha is a perennial plant which produces large oil-rich seeds beginning in the fourth or fifth year of growth. Annual production of jatropha oil per acre has been documented at a notable 202 gallons, considerably higher than rapeseed (127 gals.) or soybean (48 gals.). Jatropha is non-edible, a trait that increases its viability as a potential solution for a fuel crop. The plant is, however, cold-sensitive, and grows only in tropical and semi-tropical locations, which markedly limits its pervasiveness. Jatropha plantations aimed at biodiesel production are quickly increasing in India, Philippines, Vietnam, and several African countries.
Some species of microalgae are inherently comprised of 50% oil. Algae are the most densely growing plants on earth, yielding more per acre than any other crop. When growth factors are optimal, they can double their weight within hours. Estimates of per-acre annual yields range as high as 20,000 gallons. Even conservative estimates project yields starting at 3,600 gallons per acre per year. In comparison with other sources of oil for biodiesel, the potential of microalgae is unsurpassed.
A variety of algae species have been grown for decades as feed for aquaculture, nutritional supplements, pharmaceutical applications, and cosmetic ingredients. They are a source of pigments, proteins, enzymes, vitamins, and amino acids.
Microalgae are grown with inexpensive raw materials—sunlight, water, carbon dioxide, and horticultural nutrients—and without pesticides or herbicides. They are relatively simple to process with today's technologies.
There has been an abundance of recent publicity, along with scientific consensus,
[Technology Review, Published by MIT, Feb. 5, 2007, “Algae-Based Fuels Set to Bloom.”] that growing algae in mass culture as an alternative fuel oil source is not only viable, but possibly the best solution proposed thus far. “On a commercial scale, the economic production of biodiesel using algae is simply a no-brainer.” This statement by Nick Hodge, editor of the Green Chip Review investor's publication, echoes a widely-accepted viewpoint.
Since algae have such salient advantages as a source of oil for biodiesel, why hasn't this crop already materialized as the premier solution for today's alternative fuel dilemma? The answer is simple. Although significant effort has been expended over the past thirty years, reliable cost effective methodologies for growing high-lipid microalgae in mass culture have yet to be established. There is a long-felt but heretofore unfulfilled need for commercial production of biodiesel from algae oil in the marketplace.
The DOE Aquatic Species Program: Biodiesel from Algae
The U.S. Department of Energy (DOE) began an extensive investigation of algae as a source of biofuel oil thirty years ago. From 1978 to 1996, the U.S. Department of Energy's Office of Fuels Development funded a program to develop renewable transportation fuels from algae. The main focus of the program, known as the Aquatic Species Program (ASP) was “the production of biodiesel from high lipid-content algae grown in ponds, . . .” This statement was taken from the Executive Summary of the landmark document entitled “A Look Back at the U.S. Department of Energy's Aquatic Species Program: Biodiesel from Algae, Closeout Report”, published in July of 1998.
A summation of the NREL vision from page 10 of the report is noted as FIG. 1 Prior Art. On an algae farm, this single pond would be duplicated repeatedly, as space and resources allow. After nearly two decades of research and an expenditure of more than $450M, much was revealed about hundreds of algae species that exhibited high concentrations of oil. Large-scale open ponds were built for mass culture, but according to the report, “Attempts to achieve consistently high productivities were hampered by low temperature conditions encountered at the site.” In spite of the fact that their system design did not deliver consistently high productivity, the NREL study repeatedly asserted, “A major conclusion from these analyses is that there is little prospect for any alternatives to the open pond designs . . .” and “Several decades of R&D in this field . . . have revealed no plausible alternative to this basic design” which is described as “large unlined, open, mixed raceway ponds.” NREL concluded that “The commercial experience with open mass culture ponds suggests that such systems require relatively little further engineering development.”
In lieu of seeking culturing methods that permitted control of parameters to optimize the culture of extant organisms, the NREL report proposed that the solution to achieving consistently high productivity of mass culture of algae lies in the genetic engineering of new strains of microalgae that would perform ideally in the recommended open pond systems.
The 300-page document that emerged from this two-decade study became recognized as the authoritative manual on the topic of ‘Biodiesel from Algae.’ Many subsequent researchers followed the guidelines set forth in the NREL study. Companies continue to propose the production of oil from algae for biodiesel using huge open ponds and seeking genetically engineered strains.
Although the DOE's NREL algae research project terminated in 1996 due to curtailed funding, their efforts to produce biofuel from algae oil were revived in 2007 through a collaborative agreement with Chevron Oil Company. “Chevron and NREL scientists will collaborate to identify and develop algae strains that can be economically harvested and processed into finished transportation fuels . . . .”
Skepticism and negativism were lasting effects of the absence of consistent results from the NREL study. In 2007 one energy columnist wrote on the Biopact website, “Most of the algae companies have never proved that the technology works on a continuous basis and/or on a large scale.” “Open ponds were seen as the only viable option, but came with many drawbacks (such as contamination with rival organisms and pollution).” “Since the discontinuation of most algae-biofuel research in the 1990s, there have been no major biotech breakthroughs in the field.”